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    <periodOfReport>2026-01-23</periodOfReport>

    <notSubjectToSection16>true</notSubjectToSection16>

    <issuer>
        <issuerCik>0001454789</issuerCik>
        <issuerName>Astria Therapeutics, Inc.</issuerName>
        <issuerTradingSymbol>ATXS</issuerTradingSymbol>
    </issuer>

    <reportingOwner>
        <reportingOwnerId>
            <rptOwnerCik>0001331860</rptOwnerCik>
            <rptOwnerName>LAPOINTE ANTHONY GREGG</rptOwnerName>
        </reportingOwnerId>
        <reportingOwnerAddress>
            <rptOwnerStreet1>C/O ASTRIA THERAPEUTICS, INC.</rptOwnerStreet1>
            <rptOwnerStreet2>22 BOSTON WHARF ROAD, 10TH FLOOR</rptOwnerStreet2>
            <rptOwnerCity>BOSTON</rptOwnerCity>
            <rptOwnerState>MA</rptOwnerState>
            <rptOwnerZipCode>02210</rptOwnerZipCode>
            <rptOwnerStateDescription></rptOwnerStateDescription>
        </reportingOwnerAddress>
        <reportingOwnerRelationship>
            <isDirector>true</isDirector>
        </reportingOwnerRelationship>
    </reportingOwner>

    <aff10b5One>false</aff10b5One>

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            </securityTitle>
            <conversionOrExercisePrice>
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            <transactionDate>
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        <derivativeTransaction>
            <securityTitle>
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                <value>9.18</value>
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                    <value>Common Stock</value>
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                <underlyingSecurityShares>
                    <value>14100</value>
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        <derivativeTransaction>
            <securityTitle>
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                <value>5.79</value>
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            </transactionDate>
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                <transactionCode>D</transactionCode>
                <equitySwapInvolved>0</equitySwapInvolved>
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                <transactionShares>
                    <value>26550</value>
                </transactionShares>
                <transactionPricePerShare>
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                </transactionPricePerShare>
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                    <value>D</value>
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                <underlyingSecurityTitle>
                    <value>Common Stock</value>
                </underlyingSecurityTitle>
                <underlyingSecurityShares>
                    <value>26550</value>
                </underlyingSecurityShares>
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    </derivativeTable>

    <footnotes>
        <footnote id="F1">These numbers have been adjusted to reflect the 1-for-6 reverse stock split the Issuer effected on August 19, 2021.</footnote>
        <footnote id="F2">Pursuant to an Agreement and Plan of Merger, dated as of October 14, 2025, by and among the Issuer, BioCryst Pharmaceuticals, Inc. (&quot;BioCryst&quot;), and Axel Merger Sub, Inc., a wholly-owned subsidiary of BioCryst, on January 23, 2026, Axel Merger Sub, Inc. merged with and into the Issuer, with the Issuer surviving and becoming a wholly-owned subsidiary of BioCryst (the &quot;Merger&quot;). At the effective time of the Merger (the &quot;Effective Time&quot;), each Issuer stock option for which the applicable exercise price was less than $13.00 (each, an &quot;In-the-Money Option&quot;) that was outstanding immediately prior to the Effective Time became fully vested and exercisable and was canceled in exchange for the payment in cash equal to the product of (i) the total number of shares of common stock subject to such canceled In-the-Money Option immediately prior to the Effective Time and (ii) the excess of $13.00 over the exercise price per share subject to each such canceled In-the-Money Option, without interest.</footnote>
    </footnotes>

    <remarks>At the Effective Time, each Issuer stock option for which the applicable exercise price was equal to or greater than $13.00 (each, an &quot;Out-of-the-Money Option&quot;) that was outstanding immediately prior to the Effective Time was canceled for no consideration, which cancelation is exempt from Section 16 of the Securities Exchange Act of 1934, as amended, pursuant to Rule 16a-4(d) and Rule 16b-6(d) thereunder. Accordingly, the Reporting Person's Out-of-the-Money Options that were canceled in the Merger are not reported herein.</remarks>

    <ownerSignature>
        <signatureName>/s/ Ben Harshbarger, as attorney-in-fact for Gregg Lapointe</signatureName>
        <signatureDate>2026-01-23</signatureDate>
    </ownerSignature>
</ownershipDocument>
